Dead connections on AIX 5.2

[polani]

Dears
I am using Progress 9.1D07 on AIX 5.2
The issue which i am facing is that lot of dead connections are producing on AIX
That is processes with pid = "-"... i can not kill them
I have to restart the server....
There are two problems appearing

These dead processes or zombie processes are hgging system performance ..cpu utlization approaches to 100% when number of these zombie processes increases
Second , as per security reasons we do not allow more than two telnet sessions on AIX... now due to zombie processess we have to allow more than two... sometimes to five or six sessions per use


Any help will be highly appreciable!!!!




Here comes polani Once again!!!

P690 Certified Specailist
HACMP & AIX Certified Specailist
AIX & HACCMP Instructor

 

[Natalie]

Polani,

We had a similar problem on AIX 4.3.3, with Progress 9.1C. We had a lot of <defunct> processes when we did "ps -ef." To solve the problem, we now run a script from the crontab to shut down all databases and reboot every Monday morning at 4:00AM.

I recommend calling IBM Software Support, because I believe this is more of an AIX issue than a Progress issue.

A little info about zombie processes:

A <defunct> process is IBM's term for what has been traditionally known as
"zombie" processes (in UNIX anyway). A "zombie" makes more sense, since it
is literally an "undead" process. Specifically, a process forks a child, and
the child process completes execution before the parent. If the parent
doesn't perform a "wait()" on the child, the dead process will sit around in
the process table until the wait() is performed. As soon as the parent
either performs a wait(), or exits the <defunct>/zombie will go away (the
"init" process automatically performs a wait() on all children when the
parent dies).

<defunct> processes take up 0 (zero) system resources outside of a slot in
the process table (i.e., they do not use memory or CPU cycles). If you see
CPU cycles associated with a <defunct> process, they are probably the cycles
accumulated by the process prior to its death. If you see a <defunct>
process _still_accumulating_ CPU cycles, GET OUT OF THERE! They've come back
to life!



Good luck!

 

[polani]

Dear,
How could you say that it is an IBM issue rather than Progress issue...
I have seen running other databases and applictions running smoothly on same version of AIX

Any other advice!

Here comes polani Once again!!!

P690 Certified Specailist
HACMP & AIX Certified Specailist
AIX & HACCMP Instructor

 

[Natalie]

Do the zombies show up as users when you Promon the database? If so, you can kill them there.